Source : Webster's Revised Unabridged Dictionary (1913)

Natant \Na"tant\, a. [L. natans, -antis, from swim, v. intens.
   fr. nare to swim: cf. F. natant.]
   1. (Bot.) Floating in water, as the leaves of water lilies,
      or submersed, as those of many aquatic plants.

   2. (Her.) Placed horizontally across the field, as if
      swimmimg toward the dexter side; said of all sorts of
      fishes except the flying fish.